Answer:18.75
Because if you combine each group of dozens you can then do 5x2.5 which equals 12.5 so then you do 1.5 of 2.5 and get 6.25
A bar graph would be a better choice because it is able to show how often he/she has gotten a good score.
10,000 - (1/2 x 10,000) - (1/4 x 10,000) - (1/10 x 10,000) = 10,000 - 5,000 - 2,500 - 1,000 = 1,500
$1,500 is being spent on staffing for the party.